The improvements and their experimental validation of a 3D-probing system for tactile dimensional metrology, introduced in 2010, are presented. The Fizeau interferometer is replaced by capacitive sensors, which enable a resolution at the probing sphere smaller than 100 nm. The results of a 2D-testing are also discussed. The simulated isotropic stiffness at the probing sphere is 84±25 N/m. The experimental stiffness is checked by force measurements and is determined to be 78±26 N/m. Requirements in design, manufacture, assembly and simulation to achieve this conformance between measured and simulated stiffness are presentedShow more